How to use TikZ externalize with PGFgantt

I recently switched on tikzexternalize on a document with several figures created by TikZ in it. Activating this Tikz library has the advantage of compiling the figures only once (if unchanged), speeding up the creation of the completed document. As a nice side benefit, one gets the images as separate PDF files, which in my case was the main motivation. One simple call to ImageMagick later, one has all images in a format of choice. However, I could not get it to work at first due to my using the PGFgantt package to create a gantt time chart. Here is the (not compiling) start point: Continue reading “How to use TikZ externalize with PGFgantt”

Finally the definitive full-frame graphic commands for beamer in LaTeX

After my two (!) previous posts on the same topic, it’s time to give my final entry for the competition of the definitive full-frame graphics command for use with beamer in LaTeX. To seal the deal, I do not propose 1, but 4 commands, depending on your use case: Continue reading “Finally the definitive full-frame graphic commands for beamer in LaTeX”

How-to make WordPress theme Twenty Sixteen completely dark

Through a custom child theme and 6 carefully built CSS rules, I have completely darkened all remaining bright elements of my WordPress installation. Here’s the result.

Roughly each year, WordPress releases a new default theme that ships with a fresh WordPress installation. As of writing, this blog relies on Twenty Sixteen. Through its Customize option, it is possible to change most colours of the theme without having to dive into the editor at all. However, this left me with some elements that were to bright for my taste: text inputs, buttons and widget borders. So I had to use some custom styles to complete the transition. Read on for all the boring details! 🙂 Continue reading “How-to make WordPress theme Twenty Sixteen completely dark”

How to only color external links in LaTeX

Package hyperref is quite handy for making a compiled LaTeX document more accessible, by allowing to quickly jump to references (back to the text with package backref), section headings (from the table of contents) and weblinks.

By default, links are marked by a coloured rectangles, which only appear on screen, not in print. If one wants to get rid of the rectangles, there are options. However, there is also the colorlinks that marks hyperlinks by changing their text colour. However, these makes all link types become coloured. There is a way to reset certain link types to the default text colour, just by setting their colour to an empty value like this:

\hypersetup{colorlinks=true,linkcolor=,urlcolor=blue}

The trick is the empty value for linkcolor. It applies to internal links (e.g. entries in the table of contents listing), which are thus not touched. This trick can be extended to the other fields citecolor, anchorcolor if needed, to either not change or change their colour.

How to launch Cygwin in the active FreeCommander directory

Under Windows, I rely on trusty FreeCommander for all my file management needs. And I use Cygwin for having my most needed shell programs nearby. Sometimes there is the need to quickly open a Cygwin terminal in the current folder within FreeCommander.Luckily, there is already a popular StackOverflow question for that. Unfortunately, most answers rely on registry editing or installing the additional chere utility. However, the answer by user Tom Kay does neither and works quite well for FreeCommander. Here is how: Continue reading “How to launch Cygwin in the active FreeCommander directory”

How to include your ownCloud calendar into Outlook (read-only)

Say you have your contacts and calendar synchronised via your own private or trusted ownCloud instance. But then at your workplace, you have to use Outlook for your work stuff. Then there is the occasional late appointment, and you run into collisions because you did not look at your private calendar before accepting a meeting invitation. What to do? Wouldn’t it be nice to see your private calendar as an overlay directly in Outlook?

Search no further, the solution is Continue reading “How to include your ownCloud calendar into Outlook (read-only)”

How to list subdirectories recursively with total size

Just a note to myself, as I always have a hard time understanding the find manpages. To list the directories and subdirectories up to a certain depth, “simply” enter:

find . -maxdepth 2 -type d

Option maxdepth states how deep the subdirectories should be listed, option type restricts output to directories (d).

If a directory listing including size is required, this much shorter snippet does the trick, using du (disk usage), the counterpart to the often-used df (disk free):

du -hd 1

Option h triggers human-readable output, replacing size byte count (5820) with SI prefixed numbers (5.8K), while d limits the recursion depth like before.

How to remap the Win button on a Microsoft Sculpt Comfort mouse

If you use the Microsoft Sculpt Comfort Desktop with its gorgeously sculpted keyboard and the round pebblestone mouse, you might not need the brightly branded “Windows” button on the mouse. Program AutoHotkey to the rescue! Simply remap the Right Windows key (that conveniently does not exist on most keyboards anyway) to any other convenient key press, script, autostring, …

In this example, I map the Browse forward action to the button, because the button below can be configured to browse backwards:

RWin::Browser_Forward

The definitive full-frame graphic command for beamer in LaTeX

2018-06-02: This content has been superseded by this newer post: Finally the definitive full-frame graphic commands for beamer in LaTeX. Look there for an updated version.

After my previous post on the same topic, I have improved upon the command considerably. This time, it is based on Matthew Leingang’s answer on the question Image on full slide in beamer package.

Usage:

\fullframegraphic[optional credits]{path/to/image}

To use, copy this definition in your preamble. Requires package tikz.

\newcommand{\fullframegraphic}[2][]{%
\begin{frame}%
\begin{tikzpicture}[remember picture,overlay]%
\node[at=(current page.center)] {%
\includegraphics[height=\paperheight,width=\paperwidth,keepaspectratio]{#2}%
};%
% optional argument: credits on lower-right corner
\ifx\relax#1\relax\else%
\node[at=(current page.south east), anchor=south east,font=\tiny,text=white,fill=black,fill opacity=.5,text opacity=1,inner sep=2pt,text height=1ex,text depth=.25ex] {#1};%
\fi%
\end{tikzpicture}%
\end{frame}}

Visual example (for the credits overlay):

fullframegraphic-DA_Cambridge_c1937

Source: File:DA_Cambridge_c1937.jpg on Wikimedia Commons

How to add subcategories to templates in WordPress

This is the snippet I have added to my category template in my blog’s child theme. I paste the following snippet usually after the taxonomy-description paragraph. This is how it looks (the two paragraphs Parents and Subcategories):

category-parents-and-subcategories

This is the code:

<?php
    // Parents
    $parents = get_category_parents($cat, true, " +++ ");
    $parents = explode(" +++ ", $parents);
    $parents = array_slice($parents, 0, -2);
?>
<?php if ( count($parents) > 0 ) : ?>
<div class="taxonomy-parents"><em>Parents:</em> <?php print(implode(', ',$parents)); ?></div>
<?php endif; ?>

<?php
    // Subcategories
    $list = wp_list_categories('depth=-1&orderby=name&style=none&echo=0&title_li=&child_of='.$cat); 
    $list = substr(trim(str_replace('<br />', ', ', $list)), 0, -1); // replace newlines by commas, trim whitespace, cut of final comma
?>
<?php if ( !preg_match("/No categorie/",$list) ) : ?>
<div class="taxonomy-subcategories"><em>Subcategories:</em> <?php echo $list; ?></div>
<?php endif; ?>

How to horizontally align beamer columns with surrounding text

If you (like me) assumed that placing two columns width 50% of textwidth next to each other would align with preceding or following text on a beamer slide, then you are mistaken (like me).

Fortunately, a discussion on Bug #262: Provide more usable columns environment showed a viable solution in form of the optional argument onlytextwidth.

However, in order to use it successfully, one must then take care of spacing oneself. Here is my result of some experimentation:

beamer-columns-to-textwidth

Here is the corresponding document source code:

\documentclass{beamer}
\usepackage{mathtools}
\usepackage{listings}
\lstset{basicstyle=\ttfamily}

\usepackage{hyperref}

\begin{document}
\begin{frame}{Testing columns spacing}{How to achieve 
correctly spaced columns with beamer}
\emph{The documentation doesn't tell you anything about 
the alignment of the columns or the space in between them.
In particular, the side effect of totalwidth (which 
changes the columns to be left aligned within the 
textarea of the slide rather than center aligned on the 
page).}
\vspace{.5cm}
\begin{columns}[t,onlytextwidth]
\begin{column}{.5\textwidth-.25cm}
This slide shows the successfull result to align the 
margins of these two columns with the surrounding text to 
exactly \lstinline{\\textwidth}.
\end{column}
\begin{column}{.5\textwidth-.25cm}
What to do?

Do your own math and specify column widths with spacing. 
These columns have equal width of 
\lstinline{.5\\textwidth-.25cm}.
\end{column}
\end{columns}
\vspace{.5cm}
From: 
\href{https://bitbucket.org/rivanvx/beamer/
issue/262/provide-more-usable-columns-environment}
{Issue \#262}: Provide more usable columns environment}
\end{frame}
\end{document}

My Python setup

In this post, I summarise my custom settings for my IPython, Matplotlib and IPython Notebook for my Windows machine at work.

IPython

First some aesthetic preferences:

# select qt backend for plotting from terminal
from IPython.terminal.ipapp import TerminalIPythonApp
TerminalIPythonApp.matplotlib='qt'

c = get_config()
# bigger plots in IPython notebooks
c.InlineBackend.rc = {'figure.figsize': (16.0, 8.0), 'savefig.dpi': 72}

These are for productivity, mainly:

# always reload packages interactively
%load_ext autoreload
%autoreload 2

# import mainly used packages
import numpy as np
import pandas as pd
import matplotlib.pyplot as plt

# change to pandas default "beautiful" style
pd.options.display.mpl_style = 'default'
# but keep sans-serif fonts (instead of monospace)
plt.rcParams['font.family'] = 'sans-serif'

Matplotlib

For coherence with my employer’s style guide, I set my plot font to Arial with the following two lines:

font.family         : sans-serif
font.sans-serif     : Arial

All this results in the following default plot appearance (here for a Pandas area plot of multiple timeseries):

ipython-pandas-area-plot

Share as Gist toolbar button

Pre-requisite: you must have a GitHub account and create a Personal access token for your share button, so that it may upload code in your name.

Once that is prepared, get the file gist.js from minrk’s ipython extensions GitHub repository and place it in in the folder .ipython/nbextensions.

Then add the following lines to file custom.js, located in your profile:

require(["nbextensions/gist"], function (gist_extension) {
    console.log('gist extension loaded');
    gist_extension.load_ipython_extension();
});

The next time you launch ipython notebook, a share button should appear in every notebook’s toolbar. The first time you click it, you must paste your GitHub access token. From there on, it will work automatically. Here is how it looks in action:

ipython-share-button

(And here is the link to the corresponding Notebook: urbs-result-plot.ipynb.)

Full-frame graphics on a LaTeX beamer presentation

2018-06-02: This content has been superseded by this newer post: Finally the definitive full-frame graphic commands for beamer in LaTeX. Look there for an updated version.

This snippet defines the custom command \fullframegraphic. Paste it into the document preamble (header) of your presentation:

\newcommand{\fullframegraphic}[1]{
\begin{frame}
\includegraphics[height=\textheight,width=\textwidth,keepaspectratio]{#1}
\end{frame}
}

Then, you can create a full-frame graphic slide anywhere (outside a frame) using

\fullframegraphic{image}

Further reading

How to git push to multiple remotes with one command

There are multiple questions with even more answers on this exact question at Stack Overflow. The simplest answer, which I failed to find again, looks like this. Add the following lines to your repo’s .git/config:

[alias]
	pushall = !git push origin master && git push github master && git push remote3 master

Simply change remote and branch names to fit yours and from thereon, a git pushall will do all the work.

How to use TikZ for inline polygons

The trick is to define inner sep=0pt when beginning the tikzpicture environment, as I learned from pgf bug report #172 minimum size in regular polygon fails for small length from last year. Here is a minimum working example, adapted to my use case of inline polygon symbols with roughly text height, i.e. 2ex in my case:

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{shapes}

\newcommand{\poly}[2]{\tikz[inner sep=0pt] {%
\node[regular polygon,%
regular polygon sides=#1,%
regular polygon rotate=#2,%
minimum size=2ex, fill] (0,0) {};}}

\begin{document}
Triangle upwards \poly{3}{0}, 
triangle downward \poly{3}{180} 
and diamond \poly{4}{45}.
\end{document}

This snippet yields the following result:

tikz-poly

How to change the default matplotlib font

The default fonts for matplotlib are set in file matplotlibrc in the folder $USER_HOME/.matplotlib. You can find them here, depending on your operating system:

  • Windows: C:\Users\YourName\.matplotlib\matplotlibrc
  • Linux: /home/YourName/.matplotlib/matplotlibrc

Within the file, search for the font section, and uncomment (remove the hash symbol # at beginning of line) or add the following settings as desired. In the shown example, I set Arial as the default:

font.family         : sans-serif
#font.style          : normal
#font.variant        : normal
#font.weight         : medium
#font.stretch        : normal

# ...

#font.serif          : Times New Roman, ...
font.sans-serif     : Arial, ...
#font.cursive        : ... cursive
#font.fantasy        : ... fantasy
#font.monospace      : ... monospace

Upon the next start of the Python interpreter, your plots should be labelled with the new font.

Further reading

How to autoreload packages while using them in IPython

I use IPython to interactively use and debug code that I edit in a text editor at the same time. Unfortunately, Python does not automatically reload packages and functions after an initial import foo, simply for performance reasons.

Fortunately, there is a solution: the IPython extension autoreload does what its name says: either all (how I use it) or only selected (imported using magic function %aimport) are refreshed, whenever I hit the Enter key. Here’s a short how-i-use-it demo, involving a minimal package foo with a helloworld function bar:

In [1]: %load_ext autoreload
In [2]: %autoreload 2
In [3]: import foo
In [4]: foo.bar()
Hello World!

In [5]: !cat foo.py
def bar():
    print('Hello World!\n')

In [6]: # edit foo.py in editor
In [7]: !cat foo.py
def bar():
    print('Hello me!\n')

In [8]: # bar() is automagically reloaded
In [9]: foo.bar()
Hello me!

How do you get it? It’s already bundled with IPython by default! Happy hacking!

How to use custom colours in LaTeX

I will post short minimum working examples (MWEs) of minimal LaTeX documents, showing a certain feature in action. Though the well-maintained LaTeX Wikibook is a much more extensive resource than a collection of such examples could ever be, they show directly compilable examples compared to isolated snippets.

I start simple: custom text colours, using different colour models. Shown here are RGB (0-255) and HTML (00-FF) style definitions. The text shows two different ways to access them. Bonus: these colours can be used in TikZ as well.

latex-xcolors

\documentclass{article}
\usepackage{xcolor}
\definecolor{cool}{RGB}{0, 110, 220}
\definecolor{heat}{RGB}{240, 120, 40}
\definecolor{pink}{HTML}{FF00FF}
\begin{document}
I am some \textcolor{heat}{really hot}, 
though \textcolor{cool}{also cold} text.
{\color{pink}Bright colors} are discouraged.
\end{document}